System level design like the other stages of product development, it is an iterative process, after you have built your first prototype you can decide later to change some features of the product to make it better. System level design is a high-level first design of your product, it should answer the question “What should the product do in order to solve the problem?”
We perform market research to validate our assumptions about the opportunity we presenting. The biggest question we need to answer here is, are enough people willing to buy what we creating to make this venture worthwhile starting? If you can answer in the affirmative then you can proceed.